This invention relates generally to methods and apparatus for tending plants, and, more particularly, relates to automatic, self-contained apparatus for sustaining plant growth.
A growing number of residential, commercial, and scientific establishments have extensive horticultural developments which require frequent monitoring and irrigation. This activity is labor-intensive, and in commercial sites, can represent a significant component of overhead cost. In the residential setting, individuals who are often away from their living space for extended periods of time cannot maintain the watering cycles of various plants in their homes, and face the possibility of damage to their plants, or the necessity of having others tend their plants. Practitioners in the field of plant research, especially in the area of hydroponics, have long recognized a need for a self-contained automatic plant tending unit.
Many plant tending systems have been proposed, and a number of automatic Plant watering and feeding devices are known in the art. The following U.S. patents provide examples of such devices:
______________________________________ 3,293,799 Keller et al 3,738,060 Jullien-Davin 3,900,134 Larson 4,060,934 Skaggs 4,148,155 Allen 4,149,340 DaVitoria-Lobo 4,185,414 Miller 4,242,835 Sorribes 4,321,937 Littlehale 4,334,386 Burcombe et al 4,527,354 Sellier 4,542,762 Littlehale 4,557,071 Fah ______________________________________
Keller et al discloses a device for automatic irrigation of plant growth chambers. When the weight of a plant growth chamber decreases below a selected point due to evaporation, valve actuation elements permit fluid to flow under the influence of gravity into the chamber.
Jullien-Davin discloses a device including a water tank adapted to support a conventional earth-filled pot, an electric pump, and associated water conduits. Water is propelled by the pump from the tank to a discharge tube having a porous intermediate section. A textile wick, in contact with the porous part of the discharge tube, conducts water by capillary action from the porous section of the tube to the earth in the pot.
Allen discloses apparatus including a pot and a sealable nutrient solution reservoir connected by a tube disposed at a selected height above the bottom of the pot. An air vent communicates with the tube, allowing air to enter the sealed reservoir when the level of nutrient solution in the pot falls below the end of the tube. This relieves vacuum in the reservoir, allowing fluid to flow into the pot until the end of the tube is again covered.
Sorribes discloses a plant growth container unit including a soil-containing receptacle surrounded by a water reservoir. A small orifice in the receptacle allows water to pass from the reservoir to the soil in the receptacle.
Burcombe et al discloses a modular hydroponic gardening system having a sump tank and plural grow tanks. Liquid is fed from the sump tank to the grow tanks by a pump located outside the sump tank.
Sellier discloses a reservoir for use with conventional plant containers for providing automatic watering capability. Water or plant nutrient solution is drawn from the reservoir by capillary wicks which contact the soil and extend into the reservoir through orifices. A feed tube is provided in communication with the reservoir for replenishing the fluids in the reservoir. The feed tube includes a float for permitting visual observation of fluid level in the reservoir.
Fah discloses a watering and feeding system for providing automatically measured amounts of water and nutrients to plants embedded in soil atop a water reservoir. Water is transported from the reservoir to the soil by capillary wicks. A water level indicator is provided.
Larsen, Skaggs, DaVitoria-Lobo, Miller, and Littlehale disclose various automatic water delivery systems.
Conventional plant watering devices, however, are generally complex and bulky. Such devices, for example, cannot conveniently be suspended without reinforced supporting structures. Certain devices, among those discussed above, depend upon capillary action to conduct water to the plants, a mechanism of water transport which can be unreliable. Other conventional plant watering devices require external sources of power for operations such as water transport, and thus cannot be self-contained. Moreover, conventional plant watering devices are often expensive, and, notwithstanding their automatic features, are inconvenient to service and refill.
It is accordingly an object of the invention to provide self-contained plant growth systems which operate without the requirement of external monitoring or external sources of power.
It is another object of the invention to provide such systems which are reliable, and convenient to operate and service.
It is a further object of the invention to provide such systems which are compact, robust and inexpensive.
Other general and specific objects of the invention will in part be obvious and will in part appear hereinafter.